Electrically-actuated track-trip



C. ApBROOKS.

ELECTRICALLY ACTUATED TRACK TRIP.

APPLICATION FILED OCT. 29,1920. Patented Apr. 5, 1921.

9 SHEETS-SHEET 1.

c. A. BROOKS.

ELECTRICALLY ACTUATED TRACK TRIP.

APPLICATION FILED OCT. 29. I920.

Patented Apr. 5, 1921.

9 SHEETS-SHEET 2.

1 21- or. WM %9 Iatented Apr. 5-, 1921.

9 SHEETSSHEET 3.

C A. BROOKS. ELECTRICALLY ACTUATED TRACK TRIP.

APPLICATION FILED OCT. 29

C. A. BROOKS.

ELECTRICALLY ACT UATED TRACK TRIP. APPLICATION FILED OCT. 29, 1920.

1,373,595. Patented Apr. 5, 1921.

9 SHEETSSHEEI' 4.

c. A. BROOKS.

ELECTRICALLY ACTUATED TRACK TRIP.

APPLICATION FILED OCT. 29| 1920. 1,373,595, Patented Apr. 5, 1921.

9 SHEETS-SHEET 5.

ELECTRICALLY AC'TUATED TRACK TRIP. APPLICATION men 0CT.29, 1920.

1,373,595. Patented Apr. 5, 1921.

9 SHEETSSHEET 6.

illlmllllllll jgi 1 I z z I 1 1. f" y 1 r I ..-.r I e \J C. A. BROOKS.

ELECTRICALLY ACTUATED TRACK TRIP.

APPLICATION FILED 061329. 1920.

Patented Apr. 5, 1921,

9 SHEETSSHEET 7- Patented Apr. .5, 1921.

9 SHEETS-SHEET 8.

= :IlllllWlllllllllI- C. A. BROOKS.

ELECTRICALLY ACTUATED TRACK TRIP.

APPLICATION FILED OCT. 29, 1920. 1,373,595.

uZtwom C. A. BROOKS.

ELECTRICALLY ACTUATED TRACK TRIP.

APPLICATION FILED OCT. 29, I920.

Patented Apr. 5, 1921.

9 SHEETS-SHEET 9.

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J J I r I l l I I I llL|+f l l l l IL CLAYTON A. BROOKS, OF GIBARD, PENNSYLVANIA.

ELECTRICALLY-AC'IUATED TRACK-TRIP.

Specification of Letters Patent.

Application filed October 29, 1920. Serial No. 420,367.

To all whom it may] concern:

Be it known that I, CLAYTON A. BROOKS, a citizen of the United States, residing at Girard, in the county of Erie and State of ennsylvania, have invented certain new and useful Improvements in Electrically- Actuated Track-Trips; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the ings, and to the letters thereon, forming part of this specification.

My invention relates to electrically actuated track trips for railroads, particularly to that class thereof which controls the operation of trains by means of block signals.

The object of my invention is to provide trip mechanism located adjacent to the track-rails of a railway which will be electrically controlled to operate safety devices carried on moving trains, of the character shown and described in U. S. Patents Nos. 1,221,826 and 1,221,827 issued to me April 10, 1917.

In carrying out the conception of my invention I provide a normally upstanding trip to be placed in the road-bed, with spring pressed means to maintain the same in an upright position so that the same may give away from the impact of a fallen brakebeam or other object not intended to be low enough to strike said trip; and I also pro vide motor actuated mechanism to cause said trip to be moved out of engaging position; that is, from the position of danger to the position of safety, and vice-versa, to correspond to the positions of the semaphores, so that when the block-semaphore shows safety to allow a train to pass, the first or positive trip will be likewise moved to the safe position so that it will not actuate the safety device on, the train, and the train will not be stopped thereby.

To guard againstpossible breakage of the trip actuating mechanism Iplace a duplicate or negative trip and actuating mechanism in the road-bed a sufficientdistance, say a half mile away, in the direction of the traffic, and the said duplicate trips and their actuating motors are so connected by electrical conductors with a common electrical generator, and with the signal circuit of the semaphores that said trips will be alternately accompanying draw of reference marked moved to safety and danger,that is,

the positive trip will be moved to danger when the semaphore shows danger, and will remain at danger so long as phore does; while the second or negative trip will remain at safety during the same period; also should the positive trip be broken down, said second or negative trip will move to danger, so that should the moving train not be stopped by the first trip it will be stopped by the second trip.

The first or positive trip being at danger when the semaphore signals danger, and the negative trip being at safety, when the signal circuit is deenergized to permit the semaphore to signal safety, the motor of the second or negative trip is enei= gized to move the negative trip to safety, and then the motor of the positive trip is energized and moved to danger and vice versa.

The several electrical circuits and switch mechanisms; as well as the details of trip mechanism suitable to embody my invention, are hereinafter fully described and pointed Patented Apr. 5, 1921. I

the semaout, and are illustrated in the accompanying the circuit energized during said movement.

Fig. 3, is a like view after the movements of 1 and 2 are completed and both positlve and negative trips at rest'in the positions indicated by broken lines in said figures, none of the circuits being energized.

Fig. 4, is a like view showing the semaphore dropped to safety, energized cir cuits in heavy lines, and the negative trip moving to danger.

Fig. 5, is a like view showing the semaphore dropped to safety, the negative trip having completed its movement to danger and at rest thereat, the positive trip moving to safety and the circuits energized during said movement.

Fig. 6, is a like view showing the energized track circuit in heavy lines while the semaphore is at safety both track trips at rest, and the remainder ofthe energized, shown by light lines.

Fig. 7, is a like view showing the enercircuits degized circuit when the negative trip has been broken down, the semaphore dropped to safety and the positive trip moving to safety.

Fig. 8, is a like view showing the energized circuits when the positive trip has been broken down, semaphore at danger, and the negative trip moving to danger instead of the positive trip.

Fig. 9, is a plan view trip mechanism.

Fig. 10, is a side elevation of the same with the motor mechanism removed therefrom.

' Fig..l1, is a vertical cross-section thereof.

Fig. 12, is a plan view of switch mechanism suitable for use with my invention.

Fig. 13, is an end View thereof.

Fig. 14, is a side view of the same.

In Figs. 9 to 11 inclusive A indicates one of the rails, and A indicates the ties of a section of rail-road. Upon the ties A ata desired point I secure a cross-bar A in which is journaled a rockable tube B having secured thereon a member B having spaced, laterally projecting ears 5, Z), be-

of my improved tween which is pivoted a swinging trip arm or plate 0, upon a plvot-pin C; the end of said arm C within said ears is provided with a segment of gear teeth 0 (see Fig. 11) and within said tube 13 is a shaft or red D provided with cylindrical rackteeth (Z, which intermesh with the segmental gear teeth 0 on the arm C, so that a longitudinal movement of the rod D. will cause said plate C to swing on the pin C as indicated by broken lines in Fig. 11. p

To give longitudinal movement to the rod D I provide a erankshaftlil upon which is placed a gear wheel E, which is engaged by a gear E which is driven motor E 7 V To maintain the trip-arm C in avertical position as shown in Fig. 11, I provide a frame F in. whichthe rear end of the tube B is mounted, and upon the tube B within said frame, an upright arm F is secured. Pivoted-within the frame F are bell crank leversG which cross'each other under the tube B, and which have their upper ends pivoted to bars G, which bars are provided with anti-friction rollers g, whichengage opposite sides of said arm F, while the lower ends of said bars G are provided with rollers g which rest in slots 7, and between the lower ends of said bell crank levers a spring H i placed, which acts to cause said bell crank levers to force the bars G up wardly against the arm. F from opposite sides and thereby yieldin'gly retain it and the trip-arm C in normally vertical position from which it may be moved bya fallen brake-beam or other like object, only to be swung back again by. the spring H after such an object has passed by, the spring H,

by an electric in my aforementioned patents.

ithin the frame F I place pairs of electric terminals 1 and J and place in one of the slots f a slide K which carries a plate.

K which is adapted to bridge a pair of said terminals I and J said slide K being connected to a bar G so that if the spring H should become broken, or fail to return the arm F to its normally vertical position, the bridge plate K will bridge the pair of terminals J. These terminals I and J are connected to the electrical circuits hereinafter described.

Between the crank-shafts E and frames F, I place a circuit changing switch mecha-,

nism shown in Figs. 12, 13 and 14, which consists of a supporting frame L in which is placed a sliding member L, through which sliding member the rod D passes. lVithin said sliding member I place upon the rod D a disk 03, which is adapted to engage the end walls of the sliding member, there being a suitable amount of lost motion provided for between said disk and said sliding member L. The slide L has, on its under side, a gear rack Z with whicha gear wheel L intermeshes, said gear wheel being fixed upon a shaft L journaled in the frame L. Upon said shaft L I place a cranlcarm M (see Figs. 13 and 14) from. the free end of which a spring M extends to a fastening on the frame L, so that when the free end of the crank M passes the dead center of the shaft L, the spring M operates to instantly throw the crank over against one of the stops lv thereby forcing the slideL to the limit of its movement.

Upon the top of the frame (see Fig. 12% 1 alace terminals N, N, N N and P, P said terminals N, etc, are provided with spring contacts 11. which extend past each adjacent terminal P andioverlap said slide L so that at each semi-reciprocation of said slide one pairof said spring contacts a engages a pair of contacts P and P or P and P V r The diagrammatic drawings shown in Figs. 1 to 8 inclusive indicate the duplicate track trips'C and their actuating mechanism as positive and negative; the positive trlp being the first one to be approached by a moving train, and the direction of traffic is indicated by the heavy arrow. I also show in broken lines an ordinary semaphore for the purpose of explanation.

In Figs. 1 to 8 inclusive, R indicates an electric generator from which a conductor 2 leads to one side of a motor which OPGI'", ates the crank shaft E of a positive trip mechanism. Another conductor 3 leads from the other side of said generator to ture' R in contact with the terminal S.

From the terminal S a conductor 5 leads to the post N of the positive circuit chang- 'ing switch mechanism, and from the contact point P of said mechanism a conductor 6 leads to the other side of the motor above mentioned, so that when it is desired to move the positive trip arm 0 to a vertical or danger position to correspond with the danger position of the semaphore, the positive switch mechanism being in the position shown in Fig. 1, the circuit will be from the generator R through conductor 3, armature arm R conductor 5, spring contact a, conductor 6, motor E and conductor 2, to said generator, as illustrated by heavy lines in said Fig. 1; and will so continue 1 until thecompletion of a half turn of the crank shaft E, when the positive trip-arm C will have completed its swing to a vertical or danger position, when said circuit will be broken by the action of the circuit changing switch as shown in Fig. 2.

From the post N on the positive switch mechanism a conductor 7 leads to a contact point P on said mechanism, and from the post N a conductor 8 leads to one of the terminals I in the frame F (see Fig. 10) and from the other of said terminals I another conductor 9 leads to the post N of the negative switch mechanism; another conductor 10 leads from the contact point P of said negative switch mechanism to one pole of a motor E adapted to actuate the crank-shaft E, which operates the negative 1 trip-arm (Land from the other pole of said motor E conductor 11 leads to the conductor 2, so that with the positive and negative switch mechanism being in their respective positions shown in Fig. 2, the circuit will be from the generator B through conductor 3, armature arm R conductor 5, conductor 7, spring contact 01, conductor 8, bridge plate K (see Fig. 10), conductor 9 to the negative switch mechanism contact spring a, conductor 10 to the negative motor, conductor 11, and conductor 2 to said generator which energizes the negative motor and causes its associated crank-shaft to swing the negative trip-arm C from its vertical or danger position to safety, and when a semi-revolution of the negative crank-shaft is completed, the negative switch mechanism L will have broken the contact of its spring contact n from the con tact point P which breaks the circuit shown by heavy lines in Fig. 2, and both positive and negative trips will remain at rest as long as the semaphore remains at danger,

as shown by Fig. 3, wherein none of the circuits are energized. It will be noted by an inspection of Fig. 3 that the positive and negative switches L have caused the spring contacts a to contact against the negative contact posts P and P and against the positive contact posts P and P thus formin an open circuit from the contact point S at the relay through a conductor 12 to the post N of the positive switch mechanism, thence through the conductor 13, which extends from the contact point P of said switch mechanism to the post N of the negative switch mechanism; thence by the conductor 14 from the contact point P of said negative mechanism to conductor 10 and thence to the negative motor E and thence by the conductor 11 to conductor 2, generator R, conductor 3, post R and relayarmature R Now, when the semaphore signal circuit is energized, to cause the semaphore to drop to safety to allow the passing of a train, the relay magnet R causes the armature R to close said circuit by contacting with the contact point S which energizes said circuit as shown by heavy lines in Fig. 4, which actuates the negative mo tor E to rotate the negative crank shaft E, and thereby causes the negative trip-arm C to swing to a verticalor danger position as indicated in Fig. 4; and when said negative trip-arm C has completed its up ward travel, the circuit above described and indicated by heavy lines in Fig. 4 is broken by the negative switch L which separates the spring contact n from the negative contact P The movement of the negative switch L opening the last described circuit allows the spring contacts n to engage the negative contact points P and P thus'establishing an energized circuit from relaycontact point S through conductor 12 to post N of the positive switch mechanism; by conductor 13, conductor 16 to one of' the terminals 1 in the negative mechanism frame F (see Fig. 10) associated with the negative trip mechanism C, thence by conductor 17 to the post N of the negative switch mechanism; from contact point P of said mechanism to conductor 18, thence by conductor 18 to positive motor E thence by conductor 2 to generator R, and armature arm to relay contact point S as shown by heavy lines in Fig. 4, which energizes the positive motor E to actuate the positive trip mechanism to swing the trip arm 0 down to safety as indicated by the arrow in Fig. 5.

At the end of the downward movement of the positive trip arm C, the positive switch L breaks the circuit shown by heavy lines in Fig. 5, in which condition all of the circuits remain un-energized until the semaphore circuit S is deenergized to permit the semaphore to be raised to a safety position, as

shown in Fig. 1, when the relay armature arm is released and the spring S causes said arm'to engage the relay contact point S, which closes the energized circuit heretofore described and shown by heavy lines in Fig. 1, which again causes thepositive trlp arm C to be swung up to danger to correspond with the semaphore signal,

and the negative trip arm to be swung down to safety as shown by Figs. 2 and 3, and

heretofore described. Thus, when a train has been stopped by the positive trip arm C being at danger, and then released to proceed by the deenergizing of the semahore si nal circuit the conse uent closin P e a and energizing of the circuit shown by heavy lines in Fig. 2, causes the negative trip arm C to swing down to that the train will not be stopped thereby,

and thereafter said trip arm will remain at rest until the semaphore signal circuit S is again energized.

Now, should the spring H (see Fig. 10) in either of the duplicate positive or negative trip mechanisms fail to maintain the trip C in a vertical position by being broken so that the arms G would be in the position shown in broken lines, the bridge plate K would overlap and contact with the terminals J. In Fig. 7 the bridge plate K is shown by broken lines as contacting with the terminals J ofthe negative trip mechanism, in which case there will be a closed energized circuit from the generator B through conductor 3 to post R, thence by conductor 19 to one of the negative contacts J, thence through bridgeplate K to the other of said contacts J, and thence by conductor 20 to the contact point P of the positive switch mechanism, thence by spring contact at and post N of said positive mechanism, and conductor21 to conductor 6 and thence through the positive motor E and conductor 2 to the generator R which energizes said motor'and causes the positive trip arm to swing upward to danger.

At-the completion of the upward swing of the positive trip arm 0 the above described circuit, shown by heavy lines in Fig. 7, is broken by the action of the positive switch engaging the spring contacts 71. and lifting positive terminals J, in which case the enersafety sogized circuit will be from the generator R through conductor 19, conductor 22 to one of the positive terminals J, positive bridge plate K, conductor 23 to negative post N, spring contact n to magneticcontact point P, conductor 1 24 to conductor 14, thence through negative motor E and conductor 15 to the generator, as shown by heavy lines in F i 8, which causes the negative trip arm to be swung to a vertical danger position. At the completion of said movement, the above described circuit will be broken by the lifting of the spring contact n from contact with the negative contact point 1?, when all of the circuits will be open, and both positive and negative trips will remain. at rest until the positive trip mechanism is repaired.

The object of using two trips is two-fold:

First. If the electric circuit which governs the semaphore is out of order, the:

trips will not change, and one of them being at danger the mechanism on the passing engine will be actuated, thus indicating to the engineer that the semaphore is not working normally.

Second. If either'one of the pair of trips should break down, the other trip will be automatically moved to, and remain at,

danger, and shouldan engineer pass after the break down, the mechanism of the en gine will warn the engineer that either a train is ahead, or that the trip mechanism is out of order.

Neither trip ever moves to safety until the other has arisen to danger; thus, if snow or sleet prevents the one from moving to danger,? although the position of the semaphore would normally require it to be at safety, thus causing an unnecessary action of the automatic stop of any engine passing at that time,warning the engineer that either the trips are not working properly or that a train is ahead.

. My improved trip mechanism may be used at certain danger points to force reduced speed, in which case'they will not be electrically operated, and will have but one motion, viz :-A yielding motion to avoid breaking, should some heavy object accidentally strike them; and, to minimize the danger of breaking they can be used in pairs, as the chances of both breaking at the same time would bevery small;

When a trip is used to protect an open switch it will have two motions, the same as when usedat a semaphore, but the vertical orhorizontal position will be caused by the opening or shutting of the switch; the motion of opening or shutting the switch being imparted to the trip either by anendless cable consisting of two wires, or by means of battery, motor and electric circuit between switch and trips.

From the foregoing description it will be obvious that when the semaphore circuit is deenergized to bring the semaphore to danger the first or positive trip arm C will be caused to swing up to a danger position as shown in Figs. 1 and 2, and the second or negative trip arm C swings to safety, as shown in Fig. 3. After the train has been stopped by the danger signals, and the semaphore circuit is energized to move the semaphore to safety, the second or negative trip is swung to danger, as shown in Fig, 4, and the first or positive trip swings down to safety, as shown in Fig. 5, and the train passes onto the block after which the first or positive trip swings up to danger as shown in Fig. 1, and the second or negative trip swings down to safety, ,as shown in Fig. 2, to allow the train to pass to the next block.

Having thus shown and described suitable apparatus and mechanism to enable others to utilize'my invention, I do not desire to be limited to theexact arrangement thereof shown and described, as many modifications can be made therein without departing from the scope of my invention; therefore what I claim as new is 1. In an apparatus of the class described, a pair of shiftable trip mechanisms positioned adjacent to the railroad track, at points distant from each other, mechanism adapted to operate each of said trip mechanisms, an, electric motor to actuate each of said mechanisms, an electric generator, electric conductors connecting said generator and each of said motors, and circuit changing switches adapted to be operated by said tripoperating mechanisms so that when one of said trips is moved to a vertical position the other will be moved to a horizontal position. 7 a. V

2. In an apparatus of the class described, a pair of shiftable trips positioned adjacent to the railroad track at points distant from each other, mechanisms adapted to shift them from safety to danger, an electric motor to actuate each of said mechanisms, an electric generator, a plurality of circuit breaking switches, means actuatedby said trip shifting mechanisms to operate said circuitbreaking switches, and electric, conductors leading fromsaid generator to said circuitrbreaking switches and thence to said motors, whereby said motors will be alternately operated, and said trips will be alternately moved to danger, and means actuated by an energized semaphore signal circuit to control the operation ofsaid trip mechanisms. 7

3. In an apparatus of the class described, a pair ofshiftable trip mechanisms posi tioned adjacent to the rails of a railroad track, at points distant from each other, crank-shaft and pitman mechanisms adapt ed to operate. each of said trip mechanisms,

motor and gear mechanisms to operate said crankshafts, an electric generator, a relay magnet connected with the usual semaphore si 'na-l circuit, circuit changing means adapted to be operated by said relay magnet, electric conductors connecting said generator with the motor at each trip operating mechanism, circuit closing and breaking switches in each mechanism, and means operated by the crank-shaft and pitman mechanisms to cause said switches to alternately open and close the circuit formed by said conductors whereby said trips are alternately moved to safety and danger whensaid semaphore signal circuit is energized or deenergized.

4. In an apparatus of the class described, a pair of shiftable trip mechanisms positioned adjacent to the rails of a railroad track at points distant from each other, crank-shaft and pitman mechanism adapted to operate each of said trip mechanisms, motor and gear mechanisms to operate said crank-shafts, an electric generator, a plurality of electric conductors forming open circuits from said generator through each of said motors, circuit closing and opening switches associated with each of said trip mechanisms, means actuated by said crankshaft and pitman mechanism adapted to cause some of said switches to open some of said circuits and close others thereof, a semaphore signal circuit, a relay connected therewith, an armature arm adapted to be actuated by said relay to open one of said circuits and close another of said circuits when 7 said semaphore circuit is energized, whereby one of the above mentioned circuits is energized by said generator to cause one of said trips to be moved to safety, and then the other of said circuits is energized to cause the other of said trips to be moved to danger, and then the deenergizing of said semaphore signal circuit causes said armature arm to open that circuit and close the other circuit to cause said trips to re verse their positions. 1 i

5. In an apparatus of the class described, a pair of trips positioned adjacent to the railsof a railroad track at points distant from each other, means to yieldingly maintain said trip in a vertically'right angle position with relation to the traffic on said railroad, mechanism to cause each of said trips to swing froma vertical position to a horizontal position transverse, of said track,

crank-shaft and pitman mechanism to so operate said trips, an electric motor, and gear mechanism to actuate each of said crank-shafts, a generator, circuit changing switches associated with each of said crankshaft and pitman mechanisms, two pairs of electric terminals ateachof said trip mechanisms, a bridge-plate in each mechanism adapted to bridge a pair of terminals therein and thereby close an electric circuit,

means to cause said bridge-plate to move from contact with one pair of terminals and bridge the other pair of said terminals when the trip is broken down in the direction of traiiic, electric conductors connecting said generator and said motors through said cirarm, a contact post, a conductor from said contact post to a circuit opening and closing switch, a conductor from said switch to said motor, and from said motor to said generator, and means actuated by said crankshaftand pitman to open said switch.

7. In an apparatus of the class described, a shiftable trip, crank-shaft and pitman mechanism to operate the same, motor and gear mechanismto operate said crank shaft, a generator, a conductor leading from said generator to a relay armature arm, a contact post, a conductor from said post to a circuit opening and closing switch'post, a conductor fromsaid switch post to one side of another circuit opening and closing switch, means adapted tobe operated by said crank-shaft and pitman mechanism to open and close said switches, a conductor leading from the post ofthe last mentioned switch to the'post of a circuit opening and closing switch associated with another and duplicate trip mechanism positioned at a point distant from the first mentioned trip mechanism, crank-shaft and pitman mechanism to operate the same, means adapted to be actuated by said crankshaft and pitman mechanism to open and close said last mentioned switch, a motor to operate the same,

a conductor from said last mentioned switch to said last mentioned motor, and a conductor from said motor to said generator.

'8'. In an apparatus of the'class described, a shiftable trip, crank shaft and pitman "mechanism to operate the same, motor and gear mechanism to actuate said crank-shaft,

an electric generator, a relay armature arm,

a conductor from said generator to said arm, a contact post to receive contact from said arm, a conductor from said contact post to a circuit opening and closing switch, and

, mechanism actuated by said crank-shaft and pitman mechanism to operate said switch, a duplicate trip mechanism distant from the first mentioned trip' mechanism, a circuit changing switch in said mechanism, crank shaft and pitman mechanism for operating said trip, a motor to actuate said crankshaft, a conductor from the first mentioned and trip in avertical position.

circuit opening and closing switch to a said circuit changing switch and thence to the last mentioned circuit opening and closing switch, mechanism adapted to be actuated by said last mentioned c 'ank-shaft and pitman mechanism to open and close said switch, and a conductor from said switch to the first mentioned motor and thence to said generator. i

9. In an apparatus of the class described, a rock-shaft, a normally vertical tripfarm secured thereon, another vertical arm secured thereon, and spring pressed lever mechanism adapted to engage the last mentioned arm to maintain it in a vertical position. 7

10. In an apparatus of the class described, a rock-shaft, means to support one end thereof between a pair of railroad track-ties, a normally vertical trip arm secured thereon between the rails of a track, a frame to support the opposite end of said rock-shaft outside of said rails,'an arm on said rock-shaft within said frame, and spring pressed lever mechanism adapted to engage said last mentioned arm to maintain the same in a normally vertical position.

11. In an apparatus of the class described, a hollow rock-shaft supported in suitable hearings in transverse position to a railroad track, a trip arm pivotally secured on said shaft, a longitudinally movable rodwithin said hollow rock-shaft, and engaging said trip arm eccentrically to its pivotal connection with said rock-shaft, an arm rigidly secured on said rock-shaft, means to yieldingly' engage said arm to maintain it in upright position, and means tom'ove said longitudinally movable rod. 7 I l 12. In an apparatus of the class described, a rock-shaft, means to support the "same transversely under a rail of a railroad track, a trip arm secured on said shaft. inside of said rail, abi'furcated frame positioned outside of said rail to support one end of said shaft, another arm secured on said rock- .iechanismmounted in said frame adapted to engage and yieldingly maintain-said arm 13. In an apparatusof the lass described, a trip pivotally supported adjacent to the rails of a railroad and adapted to swing from a horizontal to a vertical position transversely of saidrailroad track, motor actuated mechanism adapted to cause said trip to swing on its pivot, an electric generator, circuits leading therefrom to said motor, circuit changing switches, and mechanism operated by said motor actuated mechanism to open some of said circuits, and close other circuits when said trip has reached'its vertical or horizontal I position. p 7 V 14. In an apparatus of the class described, a trip arm pivotally mounted to swing trans- Versely of a railroad track, crank-shaft and pitnian mechanism adapted to operate said trip-arm, motor and gear mechanism to actuate said crankshaft, an electric generator, circuit changing switches, electric circuits from said generator to said switches and thence to said motor, mechanism operated by said crankshaft and pitman mechanism to open some of said circuits so that said motor will be cut out of circuits so as to leave the cranks of said crank-shaft on a dead center with relation to said pitman, whereby said trip arm will be either at safety or danger, and said switches will close others of said circults, a semaphore signal clrcuit,

turned to danger when said semaphore is operated.

In testimony whereof I affix my signature.

CLAYTON A. BROOKS. 

